Question
M_3 A_2 is a sparingly soluble salt of molar mass y g mol^ -1 and solubility x g L^ -1 . The ratio of the molar concentration of the anion (A^ 3- ) to the solubility product of the salt is
JEE Main
Chemistry
Ionic Equilibrium
2026
JEE Main 2026 (05 April Shift 1)
JEE Main Chemistry Question (2026) — Solution
Options
- A. 1 54 y^4 x^4
- B. y^5 108 x^4
- C. 108 x^5 y^5
- D. 1 108 y^4 x^4
Answer
A. 1 54 y^4 x^4
Step-by-step solution
The molar solubility S of the salt is given by S = x y mol L^ -1 . The dissociation of the sparingly soluble salt M_3A_2 is: M_3A_2 3M^ 2+ + 2A^ 3- The molar concentration of the anion A^ 3- is: [A^ 3- ] = 2S The solubility product K_ sp of the salt is: K_ sp = [M^ 2+ ]^3 [A^ 3- ]^2 = (3S)^3 (2S)^2 = 27S^3 4S^2 = 108S^5 The ratio of the molar concentration of the anion to the solubility product is: [A^ 3- ] K_ sp = 2S 108S^5 = 1 54S^4 Substituting S = x y into the expression, we get: Ratio = 1 54 ( x y )^4 = 1 54 y^4 x^4 Answer: 1 54 y^4 x^4
Related: Chemistry — Ionic Equilibrium · All PYQ Banks